Some people care, this is why FreeBSD is still around :)
And it's not really relevant if you build your own images anyway. And in fact within the scope of FreeBSD jails offer very similar features, one of the things that's very common to do is make a base image with ZFS and then base all your jails off it. This means you just have to update your base and all your jails are updated. It's similar to pulling the latest alpine with docker. If you embrace the full ecosystem with Bastille you will have very similar capabilities.
The big missing point is that you can't use images from docker hub. This is a big negative but if you already don't plan on using those it's not really a bad thing. And there is increasing resistance to pulling things made by unknown people into production (I'm sure many vulnerabilities will happen in the future as attackers start to take advantage of this).
But anyway it doesn't have to be for everyone. It doesn't have to be the biggest thing around.